Lawyers for Ed Sheeran have responded to a copyright lawsuit over his 2015 single Photograph. The British singer's legal team argue that the $20m (£16.3m) lawsuit filed by songwriters Martin Harrington and Thomas Leonard make "scandalous allegations" and is too complicated.

Sheeran, 25, stands accused of ripping-off Matt Cardle's 2012 single Amazing, written by Harrington and Leonard, and using the melody for Photograph, which appears on the singer's chart-topping second album x (multiply). According to The Hollywood Reporter, Sheeran's lawyers claim the 44-page lawsuit is repetitive and does not clearly state a specific argument against the singer.

One of the new motions filed by Sheeran, Sony Music and Warner, reads: "Defying the most fundamental pleading requirement of providing short, concise and plain statements, the First Amended Complaint consists of 44 sprawling pages of prolix, repetitive, argumentative and scandalous allegations, made mostly on 'information and belief'.

"It makes sweeping, generalised allegations – in 156 paragraphs, some of which go on for pages and contain upwards of 25 or 30 different sentences – against eleven distinct Defendants."

Harrington and Leonard co-wrote Amazing in 2009 and it was released as a single by X Factor winner Cardle three years later. Sheeran's Photograph features on the soundtrack for romantic drama Me Before You and has been streamed over 494.7 million times on Spotify. The in-depth lawsuit includes annotations of musical notes and the chord breakdown, arguing that there are 39 notes identical to those heard in Amazing.

One motion claims the "breathtakingly long paragraphs" are a violation of a rule that statements made in lawsuits must be "short and plain". Lawyers also add: "Each Defendant is entitled to have allegations that are directed at it or him. Simply lumping Defendants together is not proper." The original lawsuit is believed to reference 11 defendants, including Snow Patrol star Johnny McDaid who co-wrote Photograph.

Listen to Ed Sheeran's Photograph:

Sheeran's legal team also argue "jurisdictional failures" given that the singer's publishing company is based in the UK and the lawsuit was filed in the US. Harrington and Leonard are being represented by Richard Busch who successfully led Marvin Gaye's family to victory when they sued Robin Thicke, Pharrell Williams and T.I. over Blurred Lines in 2015.

McDaid are Sheeran are alleged to have "copied, and exploited, without authorisation or credit, the work of other active, professional songwriters, on a breathtaking scale, unabashedly taking credit for the work of these songwriters by claiming it to be their own".

Sheeran is also at the centre of another lawsuit with his 2014 single Thinking Out Loud accused of bearing similarities to Marvin Gaye's classic Let's Get It On.

Listen to Matt Cardle's Amazing: